xsysace: Convert to bdops->check_events()

Convert from ->media_changed() to ->check_events().

xsysace buffers media changed state and clears it on revalidation.  It
will behave correctly with kernel event polling.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kay Sievers <kay.sievers@vrfy.org>

drivers/block/xsysace.c

@@ -867,12 +867,12 @@ static void ace_request(struct request_queue * q)
 	}
 }
 
-static int ace_media_changed(struct gendisk *gd)
+static unsigned int ace_check_events(struct gendisk *gd, unsigned int clearing)
 {
 	struct ace_device *ace = gd->private_data;
-	dev_dbg(ace->dev, "ace_media_changed(): %i\n", ace->media_change);
+	dev_dbg(ace->dev, "ace_check_events(): %i\n", ace->media_change);
 
-	return ace->media_change;
+	return ace->media_change ? DISK_EVENT_MEDIA_CHANGE : 0;
 }
 
 static int ace_revalidate_disk(struct gendisk *gd)
@@ -953,7 +953,7 @@ static const struct block_device_operations ace_fops = {
 	.owner = THIS_MODULE,
 	.open = ace_open,
 	.release = ace_release,
-	.media_changed = ace_media_changed,
+	.check_events = ace_check_events,
 	.revalidate_disk = ace_revalidate_disk,
 	.getgeo = ace_getgeo,
 };
@@ -1005,6 +1005,7 @@ static int __devinit ace_setup(struct ace_device *ace)
 	ace->gd->major = ace_major;
 	ace->gd->first_minor = ace->id * ACE_NUM_MINORS;
 	ace->gd->fops = &ace_fops;
+	ace->gd->events = DISK_EVENT_MEDIA_CHANGE;
 	ace->gd->queue = ace->queue;
 	ace->gd->private_data = ace;
 	snprintf(ace->gd->disk_name, 32, "xs%c", ace->id + 'a');